P222A: Barometric Pressure Sensor B Circuit

P222A is the general circuit code for a second barometric pressure sensor, B. Only some engines carry one. GM's tables for the 3.0 L twin-turbo V6 (LGW, 2018) and for 2023-2024 twin-throttle engines monitor such a sensor B, but they report its circuit faults with the more specific codes P222C (low) and P222D (high) and do not use P222A. No maker documents P222A publicly. Read it as an unspecified electrical fault of sensor B, comparable to P2226 for sensor A, which Ford now stores with a failure-type byte that tells the type of fault. CARB requires circuit monitoring of every input sensor used by an emission-relevant function. Check wiring, connector and the 5 V supply; the engine usually keeps running on sensor A or a model value.

Symptoms

• Check engine light
• Usually no noticeable change in how the engine runs

Most likely causes

• Damaged wiring or corroded connector at sensor B
• Barometric pressure sensor B defective
• Fault in the shared 5 V sensor supply

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the connector and the pressure port
2. With the engine off, compare the reading with the atmospheric pressure from the barometric sensor
3. Watch how it changes when starting and accelerating
4. Clean it with a suitable product, or replace it if it does not respond

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P222A means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• 2: Fuel injection
• 2A: Specific fault in that system

Frequently asked questions

Can I keep driving with code P222A?

You can drive with caution to a repair shop. Avoid demanding power if the car is in limp mode.

What causes code P222A?

The most common causes are: damaged wiring or corroded connector at sensor B; barometric pressure sensor B defective; fault in the shared 5 V sensor supply.

Related codes

• P222BBarometric Pressure Sensor B Circuit Range/Performance
• P222CBarometric Pressure Sensor B Circuit Low
• P222DBarometric Pressure Sensor B Circuit High
• P222EBarometric Pressure Sensor B Circuit Intermittent/Erratic
• P2226Barometric Pressure Sensor A Circuit

Sources

• law.cornell.edu: 13 CCR 1968.2
• gsi.ext.gm.com: 18OBDG03A Engine Diagnostics
• gsi.ext.gm.com: 24OBDG07

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.